Field of the Invention
The present invention relates to solid-state image sensors including focus detection pixels.
Description of the Related Art
In recent years, image capturing apparatuses, such as video cameras and electronic still cameras, have become widely available. These cameras use a charge-coupled device (CCD) image sensor or a complementary metal-oxide semiconductor (CMOS) image sensor. Furthermore, focus detection pixels having an autofocus function for automatically adjusting focus during image capture have become widely available. For example, some image capturing apparatuses detect focus by phase difference detection using pixels for detecting focus in which two or more photoelectric conversion units are disposed. Another example is disclosed in Japanese Patent Laid-Open No. 2009-105358, in which a light shielding portion is disposed on a photoelectric conversion unit to selectively receive light on the photoelectric conversion unit to detect focus.
In Japanese Patent Laid-Open No. 2009-105358, the configuration of focus detection pixels and the configuration of focus detection pixels and imaging pixel are not under sufficient study. Accordingly, the present invention provides a solid-state image sensor in which the performance of the sensor is improved from the image sensor disclosed in Japanese Patent Laid-Open No. 2009-105358.